Exploring the role of stimulus code-response modality compatibility on the spatial Stroop effect

This study investigated the compatibility of stimulus codes and response modalities and how it mediated the spatial Stroop effect. Stimulus code (word, arrow and moving dots), response modality (voice, keypress and mouse movement), directional information (left and right) and physical location (centre, left and right) of the stimulus were manipulated. Participants responded to the directional information of the stimulus. Spatial interference was expected when the stimulus' directional information and physical location were incongruent. Results showed that more compatible pairings for the three response modalities were word-voice, arrow-keypress and arrow-movement. Incongruent spatial location delayed the reaction time for all response modalities with the word, speeded up the vocal and keypress responses with the moving dots, and had no effect with the arrow. Arrow was thus recommended for conveying directional information on interfaces. This study demonstrated that spatial interference was mediated by the stimulus code, response modality and their compatibility.

This study manipulated three stimulus codes and three response modalities to examine how stimulus–response compatibility mediated the spatial Stroop effect. Spatial interference appeared with the word and moving dots, but not arrow stimulus, for vocal, keypress and mouse responses. Arrow was therefore recommended to convey directional information on an interface.